The present invention relates to an apparatus with flexible attachments for reducing drag on a vehicle having a generally planar rear surface. The use of flexible vane attachments allows the rear doors of the trailer to fully open and close effortlessly. The apparatus includes a pair of vanes, each vane having a leading edge and a trailing edge. A first flexible attachment member connects an upper end of each vane's leading edge to a side of said vehicle, while a second flexible attachment member connects a lower end of each leading edge to the vehicle side. At least one third flexible attachment member connects the trailing edge of each vane to the rear surface of the vehicle. Other additional cables may be needed for additional vane support depending on vane length and profile. The vanes redirect air flowing along the sides of the vehicle into a volume of low pressure air behind said rear surface.